feat: add a protected /api/version endpoint

[bsaurusrex]

What

Adds GET /api/version, which returns the running Tinyauth version:

{ "status": 200, "message": "Success", "version": "v5.x.y" }

Why

Closes #1160. An external update checker / monitoring tool (e.g. Argus) needs a way to read the installed version. In the issue you noted a public version endpoint is a security concern and that you'd probably "add a new protected endpoint for /api/version" — this implements exactly that.

Behaviour / security

• The handler requires an authenticated user context. An unauthenticated (or merely present-but-unauthenticated, e.g. Tailscale Authenticated: false) request gets the standard { "status": 401, "message": "Unauthorized" } body, with no version leaked.
• The route is not added to contextSkipPathsPrefix, so the context middleware still runs and populates the user context; only authenticated callers see the version.
• No change to any existing endpoint or default behaviour; purely additive.

Tests

TestContextController gains three cases for /api/version: unauthorized (no context), unauthenticated context, and authorized (returns model.Version). go vet, go test ./..., go test -race, and a GOOS=windows build all pass.

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Summary by CodeRabbit

• New Features
  • Added a version endpoint for authenticated requests. Successful responses include the application version, commit hash, and build timestamp, along with a success status and message.
  • Requests without an authenticated user context receive an unauthorized status and do not receive version information.
  • Unexpected errors while creating user context are logged.

[coderabbitai]

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Reviewing files that changed from the base of the PR and between 07d9be5 and 564b47e.

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📒 Files selected for processing (2)

• internal/controller/context_controller.go
• internal/controller/context_controller_test.go

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📝 Walkthrough

Walkthrough

The controller adds a protected /api/version endpoint. Authenticated requests receive the version, commit hash, and build timestamp with HTTP 200. Requests without an authenticated context receive HTTP 401.

Changes

Version endpoint

Layer / File(s)	Summary
Response contract and route internal/controller/context_controller.go	Adds the VersionResponse shape and registers the version route.
Authentication and version response internal/controller/context_controller.go, internal/controller/context_controller_test.go	Returns HTTP 401 when context creation fails or the context is unauthenticated. Authenticated requests receive the version, commit hash, and build timestamp. Tests cover these responses.

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Feature

Suggested reviewers: flbraun

Sequence Diagram(s)

sequenceDiagram
  participant Client
  participant Router
  participant versionHandler
  participant UserContext
  participant model
  Client->>Router: GET /api/version
  Router->>versionHandler: Dispatch request
  versionHandler->>UserContext: Create user context
  alt Context is authenticated
    versionHandler->>model: Read version, commit hash, and build timestamp
    versionHandler-->>Client: HTTP 200 with success response
  else Context creation fails or context is unauthenticated
    versionHandler-->>Client: HTTP 401 with Unauthorized response
  end

Loading

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Merge Risk: 🟡 Moderate · up to 564b4

Tools relying on /api/context/app still cannot discover the version. Confirm that switching those tools to the protected /api/version endpoint is acceptable before merging.

Pre-merge checks | 2 | 3

❌ Failed checks (3 warnings)

Check name	Status	Explanation	Resolution
Linked Issues check		Issue #1160 requires the installed Tinyauth version in GET /api/context/app. The PR adds GET /api/version instead. AppContextResponse and appContextHandler do not include a version field. The …	Add the installed version to AppContextResponse and appContextHandler. Add a test that verifies the version in /api/context/app. Keep the protected endpoint only if issue #1160 explicitly changes its required endpoint.
Out of Scope Changes check		The PR adds a new protected GET /api/version API contract and tests. Issue #1160 specifies /api/context/app as the endpoint for the version. The separate route is not required by the linked issue …	Remove the separate /api/version implementation and its tests, or update issue #1160 to explicitly include this separate endpoint before retaining it.
Docstring Coverage		Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely describes the main change: adding a protected /api/version endpoint.

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Full details: Linked Issues check

Explanation

Issue #1160 requires the installed Tinyauth version in GET /api/context/app. The PR adds GET /api/version instead. AppContextResponse and appContextHandler do not include a version field. The added tests cover only /api/version.

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Full details: Out of Scope Changes check

Explanation

The PR adds a new protected GET /api/version API contract and tests. Issue #1160 specifies /api/context/app as the endpoint for the version. The separate route is not required by the linked issue and does not implement the specified endpoint contract.

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[coderabbitai]

Actionable comments posted: 1

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• 🪄 Fix CodeRabbit comments on this PR

🤖 Prompt to fix review comments

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Inline comments:
Review comments at @internal/controller/context_controller.go:
- Around line 116-118: Add the installed version to the `/api/context/app`
response by adding a version field to `AppContextResponse` and populating it
from `model.Version` in `appContextHandler`. Keep the existing `/api/version`
route unchanged.

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📥 Commits

Reviewing files that changed from the base of the PR and between 8d99068 and 8e5aa14.

📒 Files selected for processing (2)

• internal/controller/context_controller.go
• internal/controller/context_controller_test.go

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[bsaurusrex]

On the CodeRabbit "Linked Issues" / "Out of Scope" warnings (the issue title mentions /api/context/app):

This intentionally implements the version as a new protected /api/version rather than extending /api/context/app, following your direction in the issue thread:

it would have to be protected, not available to everyone … a public version endpoint gives an attacker an easy way to see if any vulnerabilities are present in that version

Nope, the app context endpoint is public by design to provide the necessary information for the frontend to work for unauthenticated users.

we can do it at the /api/user/context endpoint or we can just add a new protected endpoint for /api/version (I will probably do the second one).

/api/context/app is in contextSkipPathsPrefix (served to unauthenticated clients), so adding the version there would be the public exposure you flagged. /api/version is kept out of the skip list and gated on an authenticated context, which matches "the second one". Happy to switch to /api/user/context instead if you'd prefer that option — just say the word.

The docstring-coverage warning is addressed in the latest commit.

[steveiliop56]

Also please remove the excessive comments (L116-L119 and L163-L166), the code is quite self explanatory.

[bsaurusrex]

Thanks for the review. Both points are addressed in 564b47e: commit hash and build timestamp added to the response, and the comments at L116-L119 / L163-L166 removed.